LDS and Nitrox fills.

[MXGratefulDiver]

Sounds like a simple lack of communication on the part of both operator and diver ... and a cheap lesson in how to go about getting your tanks filled with nitrox when you already have a partial air fill.

Yes, the tank filler should have analyzed your tank first to see what was in it before they started. But you assumed they would do that, and that turned out to be a wrong assumption. Next time, either do what's already been mentioned and empty the tank first or mark your tank contents on the shoulder with a piece of tape ... or simply tell the guy when you drop off the tank that it's got air in it and you want EAN32.

Communication is free ... and it often resolves misunderstandings before they happen.

FWIW - an acceptable nitrox fill is +/- 1% of what you asked for ... you'd have been completely within your rights to tell the guy it was unacceptable and request that they adjust it to within acceptable limits. I've done that a few times when the EAN percentage wasn't what I asked for.

... Bob (Grateful Diver)

 

[Redshift]

I am with brando, it was not their fault, and it is also not traumatic, empty your tank before the next fill

I have heard of dive shops which won't fill a tank arriving empty because they say it could have been emptied during the dive and water could have gotten in. So they only fill it after a visual inspection.

 

[AfterDark]

I have heard of dive shops which won't fill a tank arriving empty because they say it could have been emptied during the dive and water could have gotten in. So they only fill it after a visual inspection.

That's true everybody is trying to make money. The LDS I go to wouldn't do that to me but, some stranger, maybe.

 

[MXGratefulDiver]

I have heard of dive shops which won't fill a tank arriving empty because they say it could have been emptied during the dive and water could have gotten in. So they only fill it after a visual inspection.

Dive shops have the freedom to make that decision ... and we as customers have the freedom to decide whether or not such a shop is worthy of our business.

If a dive shop is concerned about such things, it's simple enough to pull the valve, drop a light inside, and see if there's any moisture in the tank. If not, then I don't see the need for a full VIP (assuming the tank's VIP sticker is current). Put the valve back on and fill the tank. That whole procedure takes less than a minute, and shouldn't result in a fee ... if it does, then you're dealing with a dive shop that's more interested in short-term profits than in your safety.

... Bob (Grateful Diver)

 

[dmoore19]

Isn't it great that we have all these tools at our fingertips to communicate with others, cell phones, emails, txt messages, internet and yet we somehow can't take a minute and communicate with someone face to face and tell them what we want.

 

[MXGratefulDiver]

Isn't it great that we have all these tools at our fingertips to communicate with others, cell phones, emails, txt messages, internet and yet we somehow can't take a minute and communicate with someone face to face and tell them what we want.

... so ... send the tank monkey a text message ...

... Bob (Grateful Diver)

 

[TSandM]

In the Seattle area, you found a shop that banks 32% . . . Forgive them this miscommunication error, and consider yourself lucky. We are down to thin pickings on banked Nitrox these days.

 

[Searcaigh]

There are no banked Nitrox shops in UAE, all fills are mixed at the shops, and when you bring a tank in for a fill they empty it first then fill it with what you order.

I can totally understand if somebody brings in a pressurised tank and asks the shop to fill it with banked 32% then that is exactly what the shop will do unless they are instructed otherwise i.e. please empty the tank and fill with banked 32%

 

[PfcAJ]

This is a simple case of problems arising due to the limitations of colloquial English.

"I want my tank filled with 32%"

So do you want it to be filled with 32% or filled with 32%?

The LDS DID fill your tank with 32%. They added 32% till it was full. However, they didn't fill your tank with 32%, because it didn't have 32% in it when it was full.

If you give ambiguous directions, don't be shocked when your results aren't what you expect.

Often when I'm dealing with an unfamiliar shop and have a very specific request I will write down the fill instructions on a piece of paper to remove question.

For instance - "This tank needs to be at 32%@3200psi" and "Starting pressure is 1200psi. Please add 1000psi o2 (2200psi), top with air to 3600".

 

[NAM001]

Untill this comment i never looked at labels in this light. I have always taken the label as a device for the diver not the shop. I would still suspect that a shop can not use the label for contents identification. I wwas always taught that when you put on the reg the contents sticker comes off so no one confules it later as being full and that mix. When you are done witht he tank you tank it off and dont use it again till filled. I think they must test,,, fill ,,then retest. No one knows if the label is the current label or not. Now in the tech side of things thier tank is marked permanately with teh mix in the form of MOD.. mod70 is 50% O2 adn is deco. Mod 20 is pure O2 and is deco. Other tanks may have such as 21/35 on them and that should tell the filler what is in them. Then again the way techs handle thier equipment is different from rec divers. If they use different mixes they have different tanks for them. Not a complaint just a realistic observation. Probably as much difference when it comes to rec shops and tech shops. When a tank arrives with a nitrox sticker on it and no contents markings i would think the shop would have to analyze to know how to do the mix unless someone just askes for a top off. Thanks for you point of view.

This illustrates some of the reasons why we teach about the different mixing methods in nitrox courses, and why all agencies advocate contents labels with the analysis on all mixed gas cylinders. Safety issues aside, it helps avoid confusion on fills.

A mixed gas cylinder with air in it should have been marked 21.0%.

If the shop fills 32% from banked 32%, the OP's Slightrox fill would be the expected result. Only PP blending (or some other custom process) should leave you with the expectation of starting with 21% and ending with 32%.

The OP skipped the PP blending option and asked for the standard banked gas... And that's exactly what he got.

To use the gas station analogy more precisely... The OP asked the service station to fill him up with 93 octane, when he had a quarter tank of 87 octane, and was surprised to discover that meant he had something other than a full tank of 93 octane when they finished.

And we're blaming the gas station attendant?

I'm no fan of fill monkeys, and I throw dive shops under the bus every chance I get, but that just doesn't make sense...